Recent years have witnessed the discovery of multiple new cancer targets followed by an unprecedented discovery of novel molecularly targeted agents. These new drugs, as compared to conventional chemotherapeutic agents are characterized for their specificity and less toxic profile. The early clinical development of targeted therapeutics, however, continues to be an empirical toxicity driven process. It is likely that the development of targeted agents will benefit from the incorporation of pharmacodynamic (PD) endpoints in tumor biopsies. These studies may be useful for dose and schedule selection as well as to predict patient outcome. The underlying hypothesis is that targeted agents will be effective only in tumors in which the target is important and is properly inhibited by the drug. Thus far, this concept has not been incorporated into clinical trials in a uniform and informative manner. One of the limitations is the lack of well developed and validated PD markers suitable for incorporation into clinical studies. Our group has recently developed quantitative assays to predict and assess tumor response to targeted therapeutics by using a minimally invasive diagnostic procedure fine needles aspiration biopsy (FNAB) technique for tissue acquisition and processing. In this application, we propose to incorporate these markers in a clinical study of targeted agents in pancreatic cancer. The long term goal of our research team is the individualized treatment of cancer patients. The objectives of this hypothesis-generating application is to validate FNAB-based PD methods that we developed in the laboratory in a clinical trial. To this end, we will incorporate the developed methodology in a phase l/ll clinical study of an mTOR inhibitor rapamycin (Rapamune, Sirolimus, Wyeth) and a Raf/MEK/ERK inhibitor Sorafenib (BAY-439006, Bayer Pharmaceuticals) in second line pancreatic cancer conducted by the Gl Program at Johns Hopkins which has been approved and will be sponsored by Bayer Pharmaceuticals. The central hypothesis of the proposed research is that the incorporation of these assays will be informative for the development of the targeted therapeutic agents in clinical trials. For this purpose, we propose the following two Specific Aims: Specific Aim # 1. To determine the PD effects of rapamycin and/or sorafenib in tumor FNA samples collected from patients with pancreatic cancer who are treated with these drugs alone or in combination. Specific Aim # 2. To predict tumor response to rapamycin and/or sorafenib therapy before the initiation of therapy by analyzing pathway inhibition in tumor cells exposed to drugs ex vivo. We expect that this study will result in validation of the novel PD approaches and will also inform further assessment and refinement in future hypothesis testing studies. [unreadable] [unreadable] [unreadable]